SynergyV8

iTrader: (1)

I once read a post by someone on this board that sung to the tune saying "Camshafts are like picking out shoes, I'd never let someone else pick for me." - - or something like that. The idea behind that is to do enough research on camshaft theory (and it IS theory) where you're able to make the decision yourself on what type of bumpstick you install.

I will give you credit though for having a nice, narrow range of cams to pick from. I am glad to see there's no 23x/24x duration cam in the same sentence as a 196/207 asking which one is best...whoops, just did.

I vote for a custom grind, because none of those cams are a be-all camshaft. The 206/212 from Comp is close. If I were in your shoes I'd pick either the 114 or the 112 version on the basis of personal preference for how you think a motor should run and toss the others aside. If I could custom grind a magic stick for your 5.3L, it would be on slightly more aggressive lobes and look something like a 208/214 0.554/0.559 on a 112 LSA and 110 ICL. If you wanted better vacuum at idle and improve top end a little, I'd grind that same cam on a 115 +3 instead, but it would not make as much low end nor as much cylinder pressure as the 112 version. A good tuner can smoothen out the roughest of camshafts, I wouldn't let a cam labeled as a "choppy idle cam" scare you.

snwmn984

iTrader: (3)

I don't know if i would compare choosing a cam and choosing shoes. I can pick a pair of shoes! But i would say there is a little more sceince in picking a cam.

I know that i dont want or need a big cam, more of a nice streetable, realistic cam. I know the 206/212 cam will probably be more "torquey" down low, but i don't want to put it in and wish i would have went a little bigger. I will def. think about a custom grind.

I am in no hurry to stick a cam in, as i'm currently laid off, but this is something i want to do late spring/early summer. Keep em commin guys!

snwmn984

iTrader: (3)

So i am thinking now maybe a small stall, 2600? where would that put me?

SynergyV8

iTrader: (1)

If you look at where the stock 5.3L cam specs fall on the tach, the 190/191 duration camshaft starts to peter out around 4800-5000. The 196/207 6.0L cam starts to run out of breath about the same time but with 39 more cubic inches. This gives us a little something to work with when we factor in the displacement of the 5.3L. The 6.0L cam in a 5.3L would raise the rpm band of the 5.3L a few hundred rpm's to about 5500 or so. That's not that big of a change, especially when comparing camshafts still under .500" of lift. With small duration cams, you want the extra lift and valve timing to enhance the cylinder pressure within the given RPM range you're trying to boost up. Cylinder pressure makes torque, and torque makes fun.

So, where to next? Now is when you start looking at other members on here who have installed a similar cam into the same displacement motor as you have with the mind frame that a 196/207 cam will bring a 5.3L up roughly 500 rpms from stock. Check out their videos and see where the tach starts to fluff off, if any, during the RPM range you're interested in. For this towing/daily driver/fun at times truck, an idle-6100 RPM range is plenty. Make the same variable degree duration jump we made from the 5.3 to 6.0 cam and you have a 20x/21x duration cam with roughly an additional 500 RPM's of room on the tach.

At this point, duration is not as important as getting your valve events right. A 206/212 is not going to be any bit different than a 208/214. The reason why I chose the 208/214 specs is because Comp makes a nice set of Xtreme RPM "high lift" in a 208* and 214* style. Combine those two lobes for your intake and exhaust, then follow up with mixing and matching valve events until you have a cam that suits your goals. A 208/214 duration cam will have a power band between 800 and about 6150, especially with ~.550" lobe lift. Go any wilder and you start to bleed off too much compression and you'll lose that valuable low end pulling power which separates a truck from the car on the trailer being pulled by said truck.

Call up Comp Cams when you're ready and mention that cam I spec'd above. Let them plug away at it and improve upon it and I'm confident you'll have a great all-around camshaft when you've made your purchase. I'm by no means a camshaft guru or expert, nor claim to be one. What I am especially interested in though, is making torque and lots of it for truck applications. At least by calling Comp Cams, you get to talk to guys who get paid to do what I enjoy talking about, designing and then eventually building; truck engines.

snwmn984

iTrader: (3)

Wow, i had to read that a few times, honestly. That is probably the best advice i have gotten! i don't see how you got the 20*/21*. What about LSA? 112? and you said if you want better idle vacuum go with a 115+2? Whats the deal with this?

Ya, i really don't neccessarily need the truck to wind past 6grand. This truck will get me to work every day, pull the boat, and a few trips to the track, so idle to 6 would be a very good range.

sonoma43

iTrader: (1)

I agree with synergyv8 for the most part, I would go with something around a 206/212 a step bigger if going with that 2600 stall. I would keep that lsa around a 114 with a couple degree's of advance ground in. I would reccomend a low lift cam though, something in the .52x to .53x range in there somewhere anyway.
With similar specs you will be gaining some low end and most definately picking up mid range great for accelerating when towing!

stock48

iTrader: (16)

ISKY: 210/216 @.050'', .532''/.532'' 112*

ISKY: 212/218 @.050'', .561''/.570'' 112*

ISKY: 206/212 @.050'', .553''/.561'' 112, or 110*

They have all those lobes in .532'' also. I would stay around ~.530'' if you are towing more than racing. The high lift won't hurt your low end, but the lower lift will be easier on valve springs etc

snwmn984

iTrader: (3)

Oh boy...

Synergy, hopefully i can get a custom grind from comp, if they are still around.

snwmn984

iTrader: (3)

Dang, isky's site is down.

sonoma43

iTrader: (1)

Will be a rougher idle with those lsa's for a towing application. that 206/212 looks good, I would like to see it on a 114 though.
How aggressive are the ISKY lobes? are they comparitive at all the Comp XE-R's?